SymbItem.hs revision 3d3889e0cefcdce9b3f43c53aaa201943ac2e895
{- |
Module : $Header$
Description : parsing symbol items
Copyright : (c) Christian Maeder and Uni Bremen 2003
License : GPLv2 or higher, see LICENSE.txt
Maintainer : Christian.Maeder@dfki.de
Stability : experimental
Portability : portable
HasCASL parsable symbol items for structured specs
-}
module HasCASL.SymbItem where
import Common.Id
import Common.Token (colonST)
import Common.Keywords
import Common.Lexer
import Common.AnnoState
import Text.ParserCombinators.Parsec
import HasCASL.ParseTerm
import HasCASL.As
-- * parsers for symbols
-- | parse a (typed) symbol
symb :: AParser st Symb
symb = do
p@(PolyId i tys _) <- parsePolyId
do c <- colonST
sc <- typeScheme p
return $ Symb i (Just $ SymbType sc) $ tokPos c
<|> if null tys then return $ Symb i Nothing $ posOfId i else
fail ("bound type variables for '" ++ showId i "' without type")
-- | parse a mapped symbol
symbMap :: AParser st SymbOrMap
symbMap = do
s <- symb
do f <- asKey mapsTo
optional symbKind
t <- symb
return $ SymbOrMap s (Just t) $ tokPos f
<|> return (SymbOrMap s Nothing nullRange)
-- | parse kind of symbols
symbKind :: AParser st (SymbKind, Token)
symbKind = choice (map ( \ k -> do
q <- pluralKeyword $ drop 3 $ show k
return (k, q)) [SyKop, SyKfun, SyKpred, SyKtype, SyKsort])
<|> do
q <- asKey (classS ++ "es") <|> asKey classS
return (SyKclass, q)
<?> "kind"
-- | parse symbol items
symbItems :: AParser st SymbItems
symbItems = do
s <- symb
return $ SymbItems Implicit [s] [] nullRange
<|> do
(k, p) <- symbKind
(is, ps) <- symbs
return $ SymbItems k is [] $ catRange $ p : ps
symbs :: AParser st ([Symb], [Token])
symbs = do
s <- symb
do c <- anComma `followedWith` symb
(is, ps) <- symbs
return (s : is, c : ps)
<|> return ([s], [])
-- | parse symbol mappings
symbMapItems :: AParser st SymbMapItems
symbMapItems = do
s <- symbMap
return $ SymbMapItems Implicit [s] [] nullRange
<|> do
(k, p) <- symbKind
(is, ps) <- symbMaps
return $ SymbMapItems k is [] $ catRange $ p : ps
symbMaps :: AParser st ([SymbOrMap], [Token])
symbMaps = do
s <- symbMap
do c <- anComma `followedWith` symb
(is, ps) <- symbMaps
return (s : is, c : ps)
<|> return ([s], [])